1. Field of the Invention
The invention relates to electronic program guides and, more particularly, the invention relates to a technique for encoding a user interface of an information distribution system.
2. Description of the Background Art
In several communications systems, the data to be transmitted is compressed so that the available transmission bandwidth is used more efficiently. For example, the Moving Pictures Experts Group (MPEG) has promulgated several standards relating to digital data delivery systems. The first, known as MPEG-1 refers to ISO/IEC standards 11172 and is incorporated herein by reference. The second, known as MPEG-2, refers to ISO/IEC standards 13818 and is also incorporated herein by reference. A compressed digital video system is described in the Advanced Television Systems Committee (ATSC) digital television standard document A/53, and is incorporated herein by reference.
The above-referenced standards describe data processing and manipulation techniques that are well suited to the compression and delivery of video, audio and other information using fixed or variable rate digital communications systems. In particular, the above-referenced standards, and other “MPEG-like” standards and techniques, compress, illustratively, video information using intra-frame coding techniques (such as run-length coding, Huffman coding and the like) and inter-frame coding techniques (such as forward and backward predictive coding, motion compensation and the like). Specifically, in the case of video processing systems, MPEG and MPEG-like video processing systems are characterized by prediction-based compression encoding of video frames with or without intra- and/or inter-frame motion compensation encoding.
Over the past few years, television has seen a transformation in a variety of means by which its programming is distributed to consumers. Cable television systems are doubling or even tripling system bandwidth with the migration to hybrid fiber coax (HFC) cable plant thereby offering a larger number of channels to the viewer. Customers unsatisfied with their local cable systems have switched in high numbers to direct broadcast satellite (DBS) systems. And, a variety of other approaches have been attempted focusing primarily on high bandwidth digital technologies, intelligent two way set top boxes, or other methods of trying to offer service differentiated from standard cable and over the air broadcast systems.
With this increase in bandwidth, the number of programming choices has also increased. Leveraging off the availability of more intelligent set top boxes, several companies such as Starsight and Prevue Guide have developed elaborate systems for providing an interactive listing of a vast array of channel offerings, expanded textual information about individual programs, the ability to look forward to plan television viewing as much as several weeks in advance, and the option of automatically programming a VCR to record a future broadcast of a television program.
Unfortunately, the existing program guides have several drawbacks. They tend to require a lot of memory, some of them needing upwards of one megabyte of set top terminal (STT) memory. They are very slow to acquire their current database when they are activated for the first time or are subsequently restarted (e.g., a large database may be downloaded to a STT using only a vertical blanking interval (VBI) data insertion technique). Disadvantageously, such slow database acquisition may result in out-of-date database information or, in the case of a pay per view (PPV) or video-on-demand (VOD) system, limited scheduling flexibility for the information provider. The user interface to existing program guides does not usually look like a typical television control interface; rather looks like a 1980's style computer display (i.e., blocky, ill-formed text and/or graphics).
Additionally, the present program guides may provide an advertising or preview region along with the program guide graphics. However, the insertion of these additional video signals is performed using an analog compositor that merely inserts (overlays) the additional imagery into the broadcast stream. The analog compositing process is accomplished and then the new analog video containing an advertisement or preview and the program guide are recorded on tape for subsequent broadcast. This compositing process is not accomplished in real time at the head end of the cable system and, consequently, the program guide can not contain targeted advertising for a particular household or a particular neighborhood or region. The program guide with its associated preview or advertising is broadcast to all subscribers connected to the head end of the cable system. Additionally, these program guides are generally passive, in that, the viewer sees the program guide information change on the screen to indicate different programs and their associated channels. However, there is no provision enabling a viewer to interact with the program guide display to scroll through the channel or channels that are available. Because such scrolling in an analog system requires a splice to a new program guide video sequence, the program guides that are interactive do not include advertising video or other video information with the program guide.
Therefore, it is desirable to provide a method and apparatus for encoding an interactive program guide.